Unlike conventional tungsten-filament lamps that operate with an internal gas pressure of about one atmosphere, the Sylvania Halogen Bulb operates with an internal gas pressure of several atmospheres. This significantly reduces the rate of tungsten evaporation. The combined effects of higher pressure and the halogen cycle give halogen lamps much longer life than that of comparable non-halogen incandescent lamps operating at the same filament temperatures. This halogen lamp will also operate at higher filament temperatures with greater luminance and efficacy.